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Diesel engine control has already become complex, and in order to meet future emissions standards (such as Euro 4) it is likely to be the control system that will provide the needed performance increment. Common rail fuel injection offers yet more degrees of freedom which will need to be exploited as new emissions standards emerge. Whatever the emissions standards, there is a need to reduce risk at the earliest stages in the development of the powertrain. This will involve early and extensive simulation of the powertrain including its control system, sensors and actuators. What is the best way to achieve this using current tools? The result lies in a combination of a phenomenological model of the engine and a flexible controls environment. To illustrate the principles of developing prototype control systems, we will use the example of the CPower environment, which is a combination of a detailed engine simulation code (GT-Power) and the Simulink simulation environment.

Recent work on thermo-electric (TE) systems has highlighted the need for refined heat transfer design as well as the long standing need for improved materials performance. Recent work on heat transfer for TE systems has shown that enhanced heat transfer is needed over and above what would normally be seen in a vehicle exhaust system. In particular a better understanding of flow development and boundary layer behaviour is needed to support new design proposals. In the meantime, recent work in TE materials suggests that with the use of skutterudites significant performance benefits can accrue over existing materials. The current generation of TE materials have non-dimensional thermoelectric figure of merit (ZT) values of around 1. Skutterudites have been demonstrated to have ZT values of about 1.4 and can maintain these values over a wider temperature range than do existing materials through the engineering of the TE device.

Increasingly tighter automotive emissions legislation not only demands advanced catalyst control for super ultra low emission vehicle (SULEV) requirements, but also a close monitoring of catalyst performance. In the present paper, a control-oriented model is proposed that uses a library of four nonlinear (NARMAX) dynamic models to predict the three-way catalyst (TWC) transient response. Each nonlinear model is optimised for use under a certain operating region. In order to identify the current operating region and select the appropriate local model for prediction, the rate of change of stored oxygen is monitored. A simplified chemical model, which is based on the dynamics of the fundamental chemical reactions that occur inside the catalyst, is used for this purpose. The developed catalyst model only requires knowledge of the upstream/downstream air-fuel ratio (AFR) and it could form the basis of an on-board catalyst monitoring and control system.